In extreme cases in may be necessary to aerodynamically relieve the airloads to allow manual trimming. Those words were used by Boeing to replace the original wording of "If other methods fail to relieve the elevator load and control column force, use the "roller coaster" technique. If nose- trim is required, raise the nose well above the horizon with elevator control. Then slowly relax the control column pressures and manually trim nose up. Allow the nose to drop to the horizon while trimming. Repeat this sequence until the airplane is in trim.
If nose-down trim is required, slowing down and extending the flaps will account for a large degree of nose-up pitch. If this does not allow manual trimming then the reverse "roller coaster" can be performed to permit manual trimming.
My guess is the average 737 pilot, including those with English as second language, wouldn't have a clue what the term "aerodynamically relieve the airloads " means. They would also never have heard of the term "roller coaster".
As far as cabin crew and passengers experiencing a sudden and uncomfortable change of G forces inherent in the roller coaster method, I would postulate that is nothing compared to be speared into the ground at high speed like the two 737 MAX.
Surely, if it was good enough for Boeing to explain the use of the roller coaster method to counter an uncommanded runaway stabiliser in the early model Boeing 737 FCTM as well as in their B707 training manuals, then it has proved a folly not to include the identical advice in future 737 models.
Last edited by Centaurus; 19th May 2026 at 05:20.